java中的多播 [英] Multicast in java

问题描述

我正在尝试编写一个简单的多播试用版。

I am trying to write a simple multicast trial.

我使用了标准代码（发件人和收件人）。

I used a standard code (sender and reciever).

我尝试了几种不同的标准代码。接收代码似乎停留在接收上（好像它没有收到任何东西）。

I tried a few different standard pieces of code. it appears that the receiving code is stuck on receive (as if it's not receving anything).

接收方：

        byte[] b = new byte[3];
    DatagramPacket dgram = new DatagramPacket(b, b.length);
    MulticastSocket socket =
      new MulticastSocket(4545); // must bind receive side
    socket.joinGroup(InetAddress.getByName("226.100.100.125"));

    while(true) {
      socket.receive(dgram); // blocks until a datagram is received
      System.err.println("Received " + dgram.getLength() +
        " bytes from " + dgram.getAddress());
      dgram.setLength(b.length); // must reset length field!
    }

发送方：

      DatagramSocket socket = new DatagramSocket();

  byte[] b = new byte[]{(byte)1,(byte)5,(byte)3};
  DatagramPacket dgram;

  dgram = new DatagramPacket(b, b.length,
    InetAddress.getByName("226.100.100.125"), 4545);

  System.err.println("Sending " + b.length + " bytes to " +
    dgram.getAddress() + ':' + dgram.getPort());
  while(true) {
    System.err.print(".");
    socket.send(dgram);
    Thread.sleep(1000);
  }

我的代码有什么问题？
* 我尝试了很多不同的IP *

感谢您的帮助。

推荐答案

网络239.0.0.0/8被指定用于管理员多播流量。如果您的所有计算机都位于同一网段，则可以使用此网络中的ip来进行多播。

The network 239.0.0.0/8 is designated for administrator multi-cast traffic. If all of your machines are on the same network segment, you can use an ip in this network to play around with multi-casting.

以下是定义这些内容的RFC：

Here is the RFC defining these:

http://tools.ietf.org/ html / rfc2365

至于发送方式......您的代码应如下所示：

As far as sending goes... Your code should look something like this:

            DatagramPacket p = ...
            MulticastSocket s = new MulticastSocket(LISTENPORT);
            InetAddress group = InetAddress.getByName(LISTENIP);
            s.joinGroup(group);
            s.send(p);
            s.leaveGroup(group);

这篇关于java中的多播的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！